Electric energy collecting contact



Patented Apr. 9, 1940 UNITED STATES PATENT OFFICE memo ENERGY corlmo'rmoCONTACT Application May 21, 1938, Serial No. 209,205

In Germany August 27, 1937 1 Claim.

My invention relates to switching devices, more particularly to thestructure and arrangement of the stationary contact members, or currentcollecting elements, of drum controllers.

- Drum controllers are well known and are utilized either to makecircuits or break circuits or do both of these operations in apredetermined sequence. Veryfrequently the drum is motor operated andthe operating sequence for the circults controlled is repeated'again andagain, as in the operation of electric signs, by the coaction of thesegments on the drum and the current collecting contacts.

I The current collecting contacts heretofore known, in general, areconstructed as so-called contact hammers, or movable fingers, which arebuilt up of a plurality of rigid metal parts pivoted on bearings andutilizing special springs to produce the required contact pressure onthe 30 segments on the controller drum. Contacts and their springs andmountings, such as have just been briefly described, are relativelylarge and when the number of circuits, or required switching positionsis very large, the switch drum is 25 very long by reason of the largenumber of relatively wide contact fingers. Of course, it is possible,without changing the contact fingers, to couple two or more drumstogether. In such case, however, the drum diameter becomes large, thecircuit connections complex, and the power to operate the drum becomescomparatively large.

One object of my invention is to provide a compact electric controller.

Another object of my invention is the provision of novel currentcollectors for drum controllers.

A further object of my invention is the provision of current collectorsfor drum controllers, so constructed as to automatically provide'theirnecessary contact pressure without the use of special biasing means.

Other objects and advantages will become more apparent from a study ofthe following specification when considered in conjunction with theaccompanying drawing, in which:

Figure 1 is an end view of a drum controller provided with my specialstationary current collecting contacts;

Fig. 2 is a side view of the structure shown in Fig. 1, but the drum isnot shown; and,

Fig. 3 is a view of a single current collecting contact not mounted.

As compared to the prior art devices, a considerable simplification isattained by my invention. According to my invention, the fixed contacts,or current collecting elements, consist of drawn material, moreparticularly elastic bronze wire.

Any other wire as alloys of silver, other alloys of copper, and anyother elastic current conducting metal is satisfactory. I have foundwrought bronze, or bronze wire, to be very satisfactory. The bronze wireelements are so mounted as to be under a deformation and to thusautomatically provide their own contact pressure At the contact regionwith the segments on the controller drum, the wire may be out at anangle and be generally disposed radially of the drum.

By the use of elastic wire strands a very large number of currentcollecting elements may be mounted adjacent each other to coact with adrum of a predetermined length. In addition the mounting for theelements is made very much simpler than the mounting for the contactfingers of the prior art.

appearance. Note Figs. 1 and 3.

Adjacent the drum, I mount a rigid support consisting of two bars 10 andl I held in spaced relation by a plurality of spacing plates l2, and

rigidly held on a base plate by means of bolts l3 Three strips ofinsulation, namely, strips 1, 8 and 9, are rigidly mounted on the platesID and H by bolts l6, I3 and M, respectively. These strips 1, 8 and 9are provided with apertures 4, and 6, respectively, the number ofapertures in each strip being determined by the number of currentcollector elements 2 it is desired to mount adjacent the drum l.

The apertures are big enough to receive the collector elements 2 withconsiderable play, but when the elements are in place, as shown in Fig.l, the assembly is not only extraordinarily simple, but each collectorelement resiliently engages the drum segments yet is otherwise held infixed position.

The resilient engagement of the elements with the drum and the constantcontact pressure of the elements against the drum is accomplished bymounting the elements 2 in the apertures 4 5 and 6 of the strips I, 8and 9, so as to be under a distorting force.

In the illustrated embodiment this distortion is accomplished by firstinserting the ends l5 of elements '2, which normally have the shapeshown in Fig. 3, into the apertures 5 and 6 in strips 8 and 9 and theninserting the ends I! into the apertures 4 in strip 1 and then drawingthe strip 7 into the position shown in Fig. 1. Ends E5 will thus be bentto take a position substantially at right angles to the main or bodyportions of their respective elements. Each element is thus firmly heldin the strips and the ends I l are urged toward the drum to give thecontact pressures desired.

lhe spacing arrangement of the plates I0 and i, as determined by spacersI2, is such that the individual wires, or current collecting elements,are not firmly clamped at any point, but by reason of the distortingaction on the wires, the wires, or current collecting elements, arefirmly held in position at the walls, or edges, of the apertures 5 and6. The ends I1, on the other hand, when the drum l is in position, arefree to move radially of the drum so that the slanting contact endsreadily follow the contour of the drum or cam and the segments, notshown, with which they coact.

With the contact elements and the mounting therefor described, it isreadily apparent that many contact elements, or current collectors. maybe disposed side by side within a given length of the mounting for thesegments with which the contact elements are to coact.

Fundamentally, my invention is complete if the current collector elementis considered as an elastic lever of the first class resilientlyengaging a controller drum and, by reason of the force with which theelement engages the drum, is held between a pair of oppositely disposededges, which edges may be considered a fulcrum and a resisting force,respectively.

In view of the compact, simple, and inexpensive construction and theconsequent reliable operation of my invention, a wide field of use isassured. My invention, however, finds special application in the controlof complex electric signs where a motor is used to operate a drum. Myinvention is, however, not limited to motor-operated controllers.

The foregoing disclosure is illustrative of my invention and is,therefore, not to be taken in a limiting sense. Others skilled in theart, particularly after having had the benefit of the teachings of mydisclosure, may readily devise other and similar contact elements andmountings therefor for accomplishing the same and also similar results.I, therefore, wish to be limited only by the scope of the claim heretoappended and by such prior art as may in fact be pertinent.

I claim as my invention:

In an electric controller, in combination, a support comprising aplurality of members and having non-aligned openings in the membershaving a given relation to each other, a generally 2- shaped one-pieceelastic current conducting element disposed in the openings so that thetwo substantially parallel portions of the Z-shaped element are engagedintermediate their ends and the main or body portion of the element isengaged adjacent the junction of one of the parallel portions and themain or body portions whereby the other parallel portion is free to movein its opening when deflected, and a controller drum adjacent the end ofthe element that is free to move so disposed as to be resilientlyengaged by the free end.

ARNO BELZ.

